// Copyright 2011 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "config.h"

#include "CCScheduler.h"

#include "TraceEvent.h"

namespace cc {

CCScheduler::CCScheduler(CCSchedulerClient* client, PassOwnPtr<CCFrameRateController> frameRateController)
    : m_client(client)
    , m_frameRateController(frameRateController)
    , m_updateResourcesCompletePending(false)
{
    ASSERT(m_client);
    m_frameRateController->setClient(this);
    m_frameRateController->setActive(m_stateMachine.vsyncCallbackNeeded());
}

CCScheduler::~CCScheduler()
{
    m_frameRateController->setActive(false);
}

void CCScheduler::setCanBeginFrame(bool can)
{
    m_stateMachine.setCanBeginFrame(can);
    processScheduledActions();
}

void CCScheduler::setVisible(bool visible)
{
    m_stateMachine.setVisible(visible);
    processScheduledActions();
}

void CCScheduler::setCanDraw(bool canDraw)
{
    m_stateMachine.setCanDraw(canDraw);

    // Defer processScheduleActions so we don't recurse and commit/draw
    // multiple frames. We can call processScheduledActions directly
    // once it is no longer re-entrant.
    m_frameRateController->setActive(m_stateMachine.vsyncCallbackNeeded());
}

void CCScheduler::setNeedsCommit()
{
    m_stateMachine.setNeedsCommit();
    processScheduledActions();
}

void CCScheduler::setNeedsForcedCommit()
{
    m_stateMachine.setNeedsForcedCommit();
    processScheduledActions();
}

void CCScheduler::setNeedsRedraw()
{
    m_stateMachine.setNeedsRedraw();
    processScheduledActions();
}

void CCScheduler::setNeedsForcedRedraw()
{
    m_stateMachine.setNeedsForcedRedraw();
    processScheduledActions();
}

void CCScheduler::setMainThreadNeedsLayerTextures()
{
    m_stateMachine.setMainThreadNeedsLayerTextures();
    processScheduledActions();
}

void CCScheduler::beginFrameComplete(bool hasResourceUpdates)
{
    TRACE_EVENT0("cc", "CCScheduler::beginFrameComplete");
    m_stateMachine.beginFrameComplete(hasResourceUpdates);
    processScheduledActions();
}

void CCScheduler::beginFrameAborted()
{
    TRACE_EVENT0("cc", "CCScheduler::beginFrameAborted");
    m_stateMachine.beginFrameAborted();
    processScheduledActions();
}

void CCScheduler::setMaxFramesPending(int maxFramesPending)
{
    m_frameRateController->setMaxFramesPending(maxFramesPending);
}

void CCScheduler::setSwapBuffersCompleteSupported(bool supported)
{
    m_frameRateController->setSwapBuffersCompleteSupported(supported);
}

void CCScheduler::didSwapBuffersComplete()
{
    TRACE_EVENT0("cc", "CCScheduler::didSwapBuffersComplete");
    m_frameRateController->didFinishFrame();
}

void CCScheduler::didLoseContext()
{
    TRACE_EVENT0("cc", "CCScheduler::didLoseContext");
    m_frameRateController->didAbortAllPendingFrames();
    m_stateMachine.didLoseContext();
    processScheduledActions();
}

void CCScheduler::didRecreateContext()
{
    TRACE_EVENT0("cc", "CCScheduler::didRecreateContext");
    m_stateMachine.didRecreateContext();
    processScheduledActions();
}

void CCScheduler::setTimebaseAndInterval(double timebase, double intervalSeconds)
{
    m_frameRateController->setTimebaseAndInterval(timebase, intervalSeconds);
}

void CCScheduler::vsyncTick()
{
    TRACE_EVENT0("cc", "CCScheduler::vsyncTick");
    m_stateMachine.didEnterVSync();
    processScheduledActions();
    m_stateMachine.didLeaveVSync();

    // Allow resource updates until next vsync tick.
    if (m_updateResourcesCompletePending)
        m_client->scheduledActionUpdateMoreResources(m_frameRateController->nextTickTimeIfActivated());
}

void CCScheduler::updateResourcesComplete()
{
    TRACE_EVENT0("cc", "CCScheduler::updateResourcesComplete");
    m_stateMachine.updateResourcesComplete();
    m_updateResourcesCompletePending = false;
    processScheduledActions();
}

void CCScheduler::processScheduledActions()
{
    // Early out so we don't spam TRACE_EVENTS with useless processScheduledActions.
    if (m_stateMachine.nextAction() == CCSchedulerStateMachine::ACTION_NONE) {
        m_frameRateController->setActive(m_stateMachine.vsyncCallbackNeeded());
        return;
    }

    // This function can re-enter itself. For example, draw may call
    // setNeedsCommit. Proceeed with caution.
    CCSchedulerStateMachine::Action action;
    do {
        action = m_stateMachine.nextAction();
        m_stateMachine.updateState(action);
        TRACE_EVENT1("cc", "CCScheduler::processScheduledActions()", "action", action);

        switch (action) {
        case CCSchedulerStateMachine::ACTION_NONE:
            break;
        case CCSchedulerStateMachine::ACTION_BEGIN_FRAME:
            m_client->scheduledActionBeginFrame();
            break;
        case CCSchedulerStateMachine::ACTION_BEGIN_UPDATE_RESOURCES:
            ASSERT(!m_updateResourcesCompletePending);
            m_client->scheduledActionUpdateMoreResources(m_frameRateController->nextTickTimeIfActivated());
            m_updateResourcesCompletePending = true;
            break;
        case CCSchedulerStateMachine::ACTION_COMMIT:
            m_client->scheduledActionCommit();
            break;
        case CCSchedulerStateMachine::ACTION_DRAW_IF_POSSIBLE: {
            CCScheduledActionDrawAndSwapResult result = m_client->scheduledActionDrawAndSwapIfPossible();
            m_stateMachine.didDrawIfPossibleCompleted(result.didDraw);
            if (result.didSwap)
                m_frameRateController->didBeginFrame();
            break;
        }
        case CCSchedulerStateMachine::ACTION_DRAW_FORCED: {
            CCScheduledActionDrawAndSwapResult result = m_client->scheduledActionDrawAndSwapForced();
            if (result.didSwap)
                m_frameRateController->didBeginFrame();
            break;
        } case CCSchedulerStateMachine::ACTION_BEGIN_CONTEXT_RECREATION:
            m_client->scheduledActionBeginContextRecreation();
            break;
        case CCSchedulerStateMachine::ACTION_ACQUIRE_LAYER_TEXTURES_FOR_MAIN_THREAD:
            m_client->scheduledActionAcquireLayerTexturesForMainThread();
            break;
        }
    } while (action != CCSchedulerStateMachine::ACTION_NONE);

    // Activate or deactivate the frame rate controller.
    m_frameRateController->setActive(m_stateMachine.vsyncCallbackNeeded());
}

}